Abstract: A cementing float valve for subterranean wells is provided wherein a wiping plug retaining sleeve is concentrically positioned on the top of a float valve and secured to an outer housing by cementitous or other drillable material. the retaining sleeve provides a downwardly facing latching surface and a seal bore disposed above the latching surface for cooperation respectively with an expandable ring and an annular seal conventionally provided on a wiping plug.

Abstract: A method and apparatus are provided for effecting the replacement of a cementing float shoe on the bottom of a well casing. A casing extension sleeve defines an upwardly facing locating shoulder and a seal bore adjacent such shoulder. A new or replacement float shoe is run into the well casing on the end of a tubular workstring and seated on the locating shoulder with an external seal engaging the casing seal bore. A plurality of radially expandable slip elements are provided in the replacement unit at a position above the external seal and such slips are retained in a retracted position by a retaining sleeve. Connection of the replacement cementing shoe to the workstring is achieved through a coupling sleeve having a threaded engagement with the replacement shoe and also being connected to the retaining sleeve.